Trimethylamine oxide. Trimethylamine oxide is widely distributed in the muscles of marine teleost fish and in the bodies of molluscs and marine oligochaetes. It has a special umami taste and is the umami component of fish. It participates in the regulation of osmotic pressure, induction and Promote mitosis and have obvious feeding-attracting and promoting effects. The effect of betaine on fish attraction is mainly used to improve the taste of fish. Betaine can be converted into methionine and hydroxybutyric acid in the human body, and methionine can synthesize toxins in fish, which is more harmful to the human body. Therefore, trimethylamine oxide is the best to lure fish.